78 citations · 845 across the 33 of their papers we have counts for
33 papers
Direct Imaging Explorations for Companions from the Subaru/IRD Strategic Program II; Discovery of a Brown-dwarf Companion around a Nearby mid-M~dwarf LSPM~J1446+4633
Taichi Uyama, Masayuki Kuzuhara, Charles Beichman +35
We report the discovery of a new directly-imaged brown dwarf companion with Keck/NIRC2+pyWFS around a nearby mid-type M~dwarf LSPM~J1446+4633 (hereafter J1446). The -band contr…
Gliese 12 b: A temperate Earth-sized planet at 12 pc ideal for atmospheric transmission spectroscopy
M. Kuzuhara, A. Fukui, J. H. Livingston +103
Recent discoveries of Earth-sized planets transiting nearby M dwarfs have made it possible to characterize the atmospheres of terrestrial planets via follow-up spectroscopic observ…
The Discovery and Follow-up of Four Transiting Short-period Sub-Neptunes Orbiting M dwarfs
Y. Hori, A. Fukui, T. Hirano +100
Sub-Neptunes with are intermediate in size between rocky planets and Neptune-sized planets. The orbital properties and bulk compositions of transiting sub-Neptunes pr…
Forming localized dust concentrations in a dust ring: DM Tau case study
Hauyu Baobab Liu, Takayuki Muto, Mihoko Konishi +8
The previous, high angular resolution 225 GHz (1.3 mm) continuum observations on the transitional disk DM Tau have resolved an outer ring at 20-120 au radii that is weakly az…
Anisotropic Ionizing Illumination from an M-type Pre-main Sequence Star, DM Tau
Yuka Terada, Hauyu Baobab Liu, David Mkrtichian +6
The powerful, high-energy magnetic activities of young stars play important roles in the magnetohydrodynamics in the innermost parts of the protoplanetary disks. In addition, the a…
A spectroscopic thermometer: individual vibrational band spectroscopy with the example of OH in the atmosphere of WASP-33b
Sam O. M. Wright, Stevanus K. Nugroho, Matteo Brogi +26
Individual vibrational band spectroscopy presents an opportunity to examine exoplanet atmospheres in detail by distinguishing where the vibrational state populations of molecules d…
Absence of extended atmospheres in low-mass star radius-gap planets GJ 9827 b, GJ 9827 d and TOI-1235 b
Vigneshwaran Krishnamurthy, Teruyuki Hirano, Eric Gaidos +20
\textit{Kepler} showed a paucity of planets with radii of 1.5 - 2 around solar mass stars but this radius-gap has not been well studied for low-mass star plane…
Multiple Rings and Asymmetric Structures in the Disk of SR 21
Yi Yang, Hauyu Baobab Liu, Takayuki Muto +9
Crescent-like asymmetric dust structures discovered in protoplanetary disks indicate dust aggregations. Thus, the research on them helps us understand the planet formation process.…
Direct Imaging Explorations for Companions around Mid-Late M Stars from the Subaru/IRD Strategic Program
Taichi Uyama, Charles Beichman, Masayuki Kuzuhara +32
The Subaru telescope is currently performing a strategic program (SSP) using the high-precision near-infrared (NIR) spectrometer IRD to search for exoplanets around nearby mid/late…
ALMA Band 6 high-resolution observations of the transitional disk around SY Cha
Ryuta Orihara, Munetake Momose, Takayuki Muto +10
In this study, we reported the results of high-resolution (0.14 arcsec) Atacama Large Millimeter/submillimeter Array (ALMA) observations of the 225 GHz dust continuum and CO molecu…
A Possible Converter to Denoise the Images of Exoplanet Candidates through Machine Learning Techniques
Pattana Chintarungruangchai, Ing-Guey Jiang, Jun Hashimoto +2
The method of direct imaging has detected many exoplanets and made important contribution to the field of planet formation. The standard method employs angular differential imaging…
Infrared Spectroscopy of free-floating planet candidates in Upper Scorpius and Ophiuchus
H. Bouy, M. Tamura, D. Barrado +15
Context: A rich population of low-mass brown dwarfs and isolated planetary mass objects has been reported recently in the Upper Scorpius and Ophiuchus star forming complex. Aims: W…
A Super-Earth Orbiting Near the Inner Edge of the Habitable Zone around the M4.5-dwarf Ross 508
Hiroki Harakawa, Takuya Takarada, Yui Kasagi +46
We report the near-infrared radial-velocity (RV) discovery of a super-Earth planet on a 10.77-day orbit around the M4.5 dwarf Ross 508 (). Using precision RVs f…
Validation and atmospheric exploration of the sub-Neptune TOI-2136b around a nearby M3 dwarf
K. Kawauchi, F. Murgas, E. Palle +51
The NASA space telescope is currently in the extended mission of its all-sky search for new transiting planets. Of the thousands of candidates that TESS is expected to deliv…
Zodiacal Exoplanets in Time (ZEIT) XIII: Planet Orbits and Atmospheres in the V1298 Tau System, a Keystone in Studies of Early Planetary Evolution
E. Gaidos, T. Hirano, C. Beichman +16
Studies of planetary systems of stars in star-forming regions and young clusters open a window on the formative stages of planetary evolution. We obtained high-cadence high-resolut…
Zodiacal Exoplanets in Time (ZEIT) XII: A Directly-Imaged Planetary-Mass Companion to a Young Taurus M Dwarf Star
E. Gaidos, T. Hirano, A. L. Kraus +21
We report the discovery of a resolved (0".9) substellar companion to a member of the 1-5 Myr Taurus star-forming region. The host star (2M0437) is a single mid-M type ($T_{eff}\app…
First Detection of Hydroxyl Radical Emission from an Exoplanet Atmosphere: High-dispersion Characterization of WASP-33b using Subaru/IRD
Stevanus K. Nugroho, Hajime Kawahara, Neale P. Gibson +23
We report the first detection of a hydroxyl radical (OH) emission signature in the planetary atmosphere outside the solar system, in this case, in the day-side of WASP-33b. We anal…
ALMA observation of the protoplanetary disk around WW Cha: faint double-peaked ring and asymmetric structure
Kazuhiro D. Kanagawa, Jun Hashimoto, Takayuki Muto +13
We present Atacama Large Millimeter/submillimeter Array (ALMA) Band 6 observations of dust continuum emission of the disk around WW Cha. The dust continuum image shows a smooth dis…
Precision radial velocity measurements by the forward-modeling technique in the near-infrared
Teruyuki Hirano, Masayuki Kuzuhara, Takayuki Kotani +15
Precision radial velocity (RV) measurements in the near-infrared are a powerful tool to detect and characterize exoplanets around low-mass stars or young stars with higher magnetic…
Zodiacal Exoplanets in Time. XI. The Orbit and Radiation Environment of the Young M Dwarf-Hosted Planet K2-25b
E. Gaidos, T. Hirano, D. J. Wilson +20
M dwarf stars are high-priority targets for searches for Earth-size and potentially Earth-like planets, but their planetary systems may form and evolve in very different circumstel…
Limits on the Spin-Orbit Angle and Atmospheric Escape for the 22 Myr-old Planet AU Mic b
Teruyuki Hirano, Vigneshwaran Krishnamurthy, Eric Gaidos +19
We obtained spectra of the pre-main sequence star AU Microscopii during a transit of its Neptune-sized planet to investigate its orbit and atmosphere. We used the high-dispersion n…
GW Ori: Interactions Between a Triple-star System and its Circumtriple Disk in Action
Jiaqing Bi, Nienke van der Marel, Ruobing Dong +17
GW Ori is a hierarchical triple system which has a rare circumtriple disk. We present Atacama Large Millimeter/submillimeter Array (ALMA) observations of 1.3 mm dust continuum and…
Zodiacal Exoplanets in Time. X. The Orbit and Atmosphere of the Young "Neptune Desert"-Dwelling Planet K2-100b
E. Gaidos, T. Hirano, A. W. Mann +17
We obtained high-resolution infrared spectroscopy and short-cadence photometry of the 600-800 Myr Praesepe star K2-100 during transits of its 1.67-day planet. This Neptune-size obj…
Accretion Properties of PDS 70b with MUSE
Jun Hashimoto, Yuhiko Aoyama, Mihoko Konishi +4
We report a new evaluation of the accretion properties of PDS~70b obtained with VLT/MUSE. The main difference from previous studies in Haffert et al. (2019) and Aoyama & Ikoma (201…